The invention relates to a tumbler switch adapted to be mounted in an opening in a wall of an appliance, comprising a basic part having electrical switching contacts and contact terminals and having a tumbler secured to the basic part so as to be pivotable between at least two positions, which tumbler has a splash guard, which tumbler switch can be mounted in the opening in the wall from inside the appliance, an actuating portion of the tumbler extending at least partly through the opening in the wall after mounting, in such a manner that the splash guard is disposed on the inside of the appliance near the wall, two facing side walls of the tumbler having recesses situated between the splash guard and the actuating portion of the tumbler, projections arranged on two facing edges of the opening in the wall engaging in said recesses of the tumbler after mounting, and which basic part has at least two resilient limbs whose free ends engage against an inner surface of the wall after mounting.
Such a tumbler switch is known from GB-A-1542743. The actuating portion of the tumbler of said known switch is provided with a cap to be fastened to the tumbler. When the tumbler switch is mounted the switch, without the cap being fitted on the tumbler, is mounted perpendicularly to the wall on the inside of the appliance, the actuating portion projecting at least partly from the opening in the wall. The ends of the resilient limbs bear against an inner surface of the wall. Subsequently, the cap is snapped onto the tumbler from the outer side of the wall. In two facing side walls of the cap, in the center of the cap, partly circular recesses have been formed, in which recesses the projections of the edge of the opening in the wall engage after the cap has been fitted onto the tumbler. Thus, the recess is not obtained until the cap has been fitted onto the tumbler. For mounting said switch an additional part, i.e. a cap, to be fitted from the outside of the appliance is required. In another embodiment of this switch in accordance with GB-A-1542743 the partly circular grooves are formed directly in the side walls of the tumbler. Therefore, said embodiment does not have an additional cap. This switch is mounted by pushing the switch with the actuating portion through the opening from the inner side of the wall, for which the projections and hence the edge portions bounding the opening should recede to allow the passage of the tumbler. The projections are beveled to facilitate mounting. Although this last-mentioned method is a very simple method of mounting, such a switch appears to be rather susceptible to tolerances in practice. Not only should the walls of the various parts be flexible enough to allow the switch to be mounted but, besides, removal of the switch, for example for repair purposes, is not simple.